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Talk:Longest string challenge: Difference between revisions
→bounds checking in C, take 2
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}</lang> and it aborts on the input <code>echo "aa\nbb\ncc\ndd\nee\nff\naaa" | ./a.out</code> but works if you remove any of the doubles. --[[User:Ledrug|Ledrug]] 21:28, 17 August 2011 (UTC)
:::::: I do not consider "false positives" to be a bug. That's a (very minor) efficiency issue, but the point was to avoid buffer overflows, not to squeeze every last ounce out of the buffer. So I have one extra byte in the line buffer, and an extra line buffer sized region in the big buffer. If you prefer, imagine that those particular bytes were part of other variables. --[[User:Rdm|Rdm]] 21:35, 17 August 2011 (UTC)
:::::: Eh. If it's garanteed to fail under some situations where it has the resource to succeed, it's not an efficiency issue, it's a correctness issue. It's not even hard to fix:<lang c> while (fgets(line, LINE_MAX, stdin)) {
if (!*linend) exit(1);
if (longer(last, line)) continue;
if (longer(line, last)) {
memset(buf, 1, ACCU_MAX);
buf[0]= buf[ACCU_MAX - 1] = 0;
next = buf;
}
if (!longer(bufend, line)) exit(1);
last = next;
strcpy(next, line);
while (*next) next = &next[1];
}</lang> --[[User:Ledrug|Ledrug]] 21:45, 17 August 2011 (UTC)
== Boring solution v. restrictions ==
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